During a metal working or a resin finishing process such as when cutting or grinding is performed by a machine tool, the machine tool discharges coolant and chips of metal or resin of assorted sizes. Common metal that are cut and/or machined include aluminum, brass, copper, iron, magnesium, manganese, stainless steel, etc. When the machine tool cuts or grinds metal or resin material, a coolant such as cutting oil or lubricant dissolved in water is typically used to cool the cutting or grinding instrument of the machine tool, and/or to cool the workpiece. The coolant is also used to extend the life of the cutting or grinding instrument of the machine tool. The dirty coolant that contains the metal or resin chips is discharged from the machine tool to be later treated by a chip discharge system, whereby only the chips contained in the dirty coolant are separated from the coolant and collected.
The removal of metal chips from used or dirty coolant is well known in the art. Conventionally, a chip discharge conveyor system is used to separate chips from the coolant. The chip discharge conveyor system typically includes a hinged belt conveyor designed to remove only chips from the dirty coolant discharged from the machine tool and to then discharge such chips out from a treatment tank while clean coolant filtered by a filtration drum is discharged in into another tank or receptacle. On such chip discharge conveyor system is disclosed in Japanese Unexamined Patent Application 2000-202215 published Jul. 25, 2000 entitled “Turning Carrier System Filter Device”, which is incorporated herein by reference.
One such prior art arrangement is illustrated in FIG. 8. FIG. 8 discloses a conventional chip discharge system, comprising a dirty coolant treatment tank 2 wherein dirty coolant D containing chips that are discharged from a machine tool M is charged, and an endless hinged belt 4 provided in the dirty coolant treatment tank 2 wherein the hinged belt circulates. The dirty coolant tank 2 comprises a series of adjacent metal plates 2a, 2b, 2c, 2d and 2e, which are in close proximity to and separated from the endless hinged belt 4.
When the dirty coolant D containing chips K is charged into the dirty coolant treatment tank 2, the hinged belt 4 scoops up chips from the dirty coolant treatment tank 2 and transports the scooped chips along a partition plate 6 to a chip discharge portion B to discharge the chips at a downturn belt section located at the top of the hinged belt 4, wherein the discharged chips are discharged into a chip collection box F or the like. The downturn belt section located at the top of the hinged belt 4 accommodates both a driving sprocket 4d to transmit power to the hinged belt 4 and a drive motor. A cylindrical member 5 is provided at a tail end portion A of hinged belt 4, whereby the hinged belt 4 makes an upward turn from the bottom and serves as a return of belt 4b to the top where the hinged belt serves as a transport to belt 4a. 
The dirty coolant tank has a filtration drum 8 provided with a filtration medium 8a which filters coolant retained in the dirty coolant tank to discharge the filter coolant from the tank 2. Filtered coolant C is discharged through a coolant discharge opening 8b into a clean coolant tank E, which is located outside of the dirty coolant treatment tank. The filtered coolant is collected for reuse and/or disposal. Chips which do not pass through the filtration drum 8 and remain in tank 2 are scooped up by the hinged belt 4 and discharged from the chip discharge portion B. Since the filtration medium 8a comprising the filtration drum 8 progressively clogs, a fluid dispersing means 9 is used to clean the filtration medium. The fluid dispersing means is designed to spray cleaning fluid onto filtration drum 8 to cause chips adhering to a surface of the filtration medium 8a to be blown off the filtration drum. FIG. 9 shows a structure of the fluid dispersing means 9 used in a conventional chip discharge system. As illustrated in FIG. 9, cleaning fluid supplied from a supply pipe 9a to a fluid discharge pipe 9b (which is called a spray bar) is blown out as dispersing flow S in a fan-like shape from a plurality of fluid dispersing holes 9c, each of which is provided with a nozzle to disperse and spray cleaning fluid in a fan shaped pattern.
The fluid dispersing means used in such a conventional chip discharge system typically uses filter coolant discharged from clean coolant storage tank E. The filtered coolant typically includes fine chips. These fine chips tend to gradually accumulate in the fan-shaped nozzles of fluid dispersing holes 9c and inside fluid discharge pipe 9b. This accumulation of the fine chips eventually impairs the flow of clean coolant from pipe 9b and through holes or nozzles 9c, thus impairing or preventing the function as a fluid dispersing means from being performed, i.e. cleaning chips from filtration drum 8.
The fan-shaped nozzles need to be finely fabricated to accomplish uniformly-spreading fan-shaped flow of the coolant to be sprayed out from the fluid dispersing means; however, these finely fabricated nozzles increased production costs of the fluid dispensing means and the chip discharge system. Moreover, for the purpose of adjusting the rate or momentum of dispersing flow, a device such as a valve and/or an orifice which is used to adjust the flow characteristics of the coolant through the fluid dispersing mean such as pressure and/or volume to be supplied from the fluid discharge pipe is needs to be additionally provided, which devices also results in an increase in the number of parts of the system and increased costs.
In view of the present state of chip discharge systems, there is a need for a chip discharge system that includes less parts, that is less expensive to assemble and maintain, and which improves the efficiency of chip removal from dirty coolant.